45 years of the Protection of Wrecks Act 1973

The First Wreck Designated Under the Act

For our second blog this week celebrating the 45th anniversary of the Protection of Wrecks Act 1973, enacted on 18 July 1973, where better to start than the very first wreck designated under the Act?

We welcome guest blogger Martin Read of Plymouth University, who was at school near the Cattewater Wreck during the 1970s excavations. He subsequently became an archaeological conservator for English Heritage and the Mary Rose Trust before returning to Plymouth.

He has also taken part in excavations such as the Mary Rose & Vliegent Hart. Since 2006, he has been a Licensee for the protected Cattewater Wreck, organising surveys and research work on this site carried out by local divers and University students. He has also carried out research on the 1970s excavation archive in Plymouth City Museum and Art Gallery and project manager for the Cattewater Wreck Archive Project (for Plymouth City Museum and Art Gallery), funded by English Heritage (now Historic England).

Martin writes:

Plymouth has been an important maritime port since medieval times and as a result the area is rich in marine archaeological resources. During the Medieval and Tudor periods the port carried out coastal and international trade in cargos such as salted fish, wine, cloth and tin. The Cattewater, the lower estuary of the river Plym, has been the main anchorage for Plymouth since medieval times.

The Cattewater Wreck is believed to be an unidentified armed wooden merchantman from the early Tudor period. The site was discovered in 1973 and partly excavated between 1976-8. A substantial portion of the remains of the wooden hull should still be present, buried beneath anaerobic sediments and is believed to be under no immediate threat of damage or destruction.

Underwater photograph with a green hue, centred on a shipwreck timber, and a black & white measuring pole for scale in foreground.
Timbers emerging from the silt. © the estate of Keith Muckelroy/Historic England/Plymouth City Council


Dredging for air-sea rescue craft moorings in 1973 recovered timbers and iron guns identified as being from a Tudor shipwreck. As a result, the wreck site was designated under the Protection of Wrecks Act 1973 (Order No.1), becoming the first wreck given protection by the UK Government. The designation covers a radius of 50m centring on a position of 50°21’41.4”N 04°07’27.5”W. Within this area it is an offence to tamper with, damage or remove any part of a vessel lying wrecked on or in the sea bed, or any object formerly contained in such a vessel. This includes any diving, mooring or survey without a licence from the Government.

The site was surveyed and partly excavated under Government license (1976-8). Recovered finds included structural timbers, wrought iron swivel guns on wooden beds, stone & lead shot, lead waste, ceramics, shoes, a leather purse and textiles, as well as environmental evidence, including animal and fish bones. The finds could be characterised by function as being part of the ship and its working equipment, domestic artefacts, eating and drinking equipment and stores (Redknap 1997).

The excavation results suggested that the Cattewater wreck dated to the first half of the 16th century, and has been published as being ca.1530. The vessel was interpreted as operating as an English coastal trader (Redknap 1984).

Modern colour photograph of rust-red iron cannon viewed longitudinally in its display case, with sparkly reflections on glass.
Cattewater wreck gun at Plymouth City Museum and Art Gallery in anaerobic preservative solution. © Martin Read


Modern exploration

Geophysical survey techniques mean that archaeologists can examine a wreck site without physical interference. Plymouth University teaches geophysical surveying as part of undergraduate and post-graduate degrees and, since 2006, has held a Government license to dive and to carry out geophysical surveys (including sub-bottom profiler, side-scan sonar and magnetometer surveys) of the wreck site. These have identified the probable location of the wreck to be approximately 20m east of the centre of the designated area, but still within the radius of protection. Sub-bottom profile images show the wreck to be about 1m below the seabed.

A team of local divers have been used to ground-truth targets generated by the geophysical surveys and have also carried out metal-detector and probe surveys of the site, locating the wreck in the area identified by the student surveys.

Archive Project

The archive from the 1970s excavation has been deposited in Plymouth City Museum and Art Gallery (Site Accession Number AR.1985.2). In 2011 English Heritage funded a project (under the National Heritage Protection Commissions Programme, Project Number: 5439 MAIN, Cattewater Wreck: Developing the Archive) to improve the long term care and management of the archive to modern archival standards and organisation. The principal outcome of this project was a more accessible archive, better able to survive in the long-term.

The project revealed that a significant proportion of the excavation archive (including about 50% of the finds) was missing, presenting difficulties when making any re-assessment of the site. The number of finds recovered during discovery and excavation is hard to be precise, 474 find numbers were used, but the same number was often used for multiple finds. The site database now consists of 790 artefact/sample/timber records, including 28 records of unlabelled finds.

Open archive boxes displaying stored archaeological artefacts.
Repackaging of the Cattewater Wreck Archive. © Martin Read

A great deal of effort has been spent over the years to consolidate the site archive, including the relocation of missing elements. In 2013 the National Maritime Museum added to the archive a number of finds, samples and documents that they held.

The original archaeological studies into the finds were carried out over 30 years ago and finds research into, for instance, leather and ceramics have advanced over that period. New scientific techniques are also now available which can be applied to finds, allowing new interpretations to be made about this important site.

Ship construction

The wreck is believed to be of an unidentified armed merchantman, a 3-masted carvel-built vessel of standard form, of 186-282 tons (Redknap 1984). Evidence from the site, such as ship construction and some finds (such as ceramic tiles) now indicate that the ship was built in southern Europe, perhaps somewhere in SW France, Iberia or in the western Mediterranean (perhaps as far east as western Italy).

Carbon-14 dating was carried out on two wooden samples taken from the ships structure. A futtock was dated to AD 1420-1600 (340~80 BP, 1610~80 ad uncalibrated, HAR-3310), whilst an oak outer planking sample was dated to AD 1429-1509 (510~50 BP, 1390-1490ad uncalibrated, UB-2225).

Tree ring analysis (dendrochronology) was carried out on two of the structural timbers, the keelson and a floor timber. Comparison with tree-ring chronologies suggested several potential dates but none of these were acceptable, e.g. the keelson appeared to match at two places, giving dates for its outer ring of A.D. 1454 or 1457, but with no confidence.

Neither Carbon-14 or tree ring dating really helps with the dating of the ship, at present, though they are consistent with the other evidence.

It is believed that the carvel ship construction technique reached northern Europe sometime in the second half of 15th century. Until better dating can be obtained, this is the most likely date for the construction of the ship.

Working life

The majority of the finds recovered were identified as being English and the ballast included local Plymouth limestone and granite.

No English ceramics of the 15th-16th century were originally identified from primary wreck contexts. However, reinterpretation of the ceramics has led to the identification of one sherd of Tudor Green Ware (from the Surrey/Hants border) dating to the late 15th-17thc, whilst another unstratified sherd has been identified as possibly part of a cooking pot from South Somerset.

International links are shown from imported finds, including Dutch, Rhenish (Raeren and Siegburg), SW French and Iberian ceramics. The largest group of ceramics recovered were identified as being Dutch, but both the Dutch and Rhenish ceramics were commonly traded into England at this period.

The scarcity of ceramics from Iberia cast some doubt on a possible Iberian origin for the wreck (Redknap 1997). A number of sherds of Iberian ceramics were recovered from the scour deposits, so may not be directly associated with the wreck. A possible Merida-type glazed floor tile, which are very rare in the UK, was found in a primary wreck context and probably came from the galley hearth.

Ceramics from southern Europe, particularly from South-West France, Iberia and Italy, have commonly been found in medieval and post-medieval deposits on land sites in Plymouth showing strong links between Plymouth and Mediterranean Europe, a result of the port’s international trade. It may be significant that two fragments of ceramics identified as being from SW France were found in primary wreck deposits.

The ship seems to have been re-ballasted in Plymouth, but non-local stone was identified as originating from around the Southern English coast, from Bristol/South Wales to Kent. This was used to indicate that the vessel was acting as a coastal trader, possibly operating between Bristol and London, but other interpretations are possible. The ballast makeup could reflect local ballasting practice, incorporating residual ballast from the re-ballasting of previous ships and therefore the main background trade links of the port.

Wrecking, salvage and site formation

Recent re-dating of the leather shows that the ship must have been wrecked after 1500, with the most likely date being in the early 16th century. This is consistent with the re-dating of the ceramics (ca.1480-ca.1525), though the possibility remains that the actual date of wrecking might be later.

A study of historic records shows that the most frequent cause of shipwreck in the Cattewater was whilst either at anchor or entering/leaving the port during a storm, with the Cattewater being particularly exposed during south westerly storms. These are also the most likely causes for the loss of the Cattewater Wreck.

Another possible scenario is due to fire. There is some evidence in support of this, though this comes mostly from the scour layers and may not relate to the wreck.

The only known casualty of the shipwreck was a dog, which had probably been used to control rats on the ship. Four bones have been identified, and measurements indicate a withers height of about 50cm (just over 20 inches), the height of a whippet, border collie or spaniel.

The wreck site was shallow enough for the salvage of anything of value to have taken place. As a result it is uncertain what cargo (if any) the ship was carrying at the time. Finds included barrel parts and cod bones, with a suggestion that salted fish might have been a cargo (though they are more likely to be victuals).

Stable isotope analysis, carried out on some of the cod bones by York University, indicated that most fish were likely to have come from local (or relatively local) waters, but one fish came from outside the area, most likely from the North Atlantic.

Most finds that could be directly associated with the wreck, including the dog bones, were recovered from amongst the ballast or between the ships planking, but a large number probably originating from the wreck were found in other, later, contexts having been eroded out.

Several scour pits were excavated around the wreck, ceramic finds indicating they were formed (or at least filled) after 1700, most likely in the early 18th century.

Present Interpretation

The original scenario put forward as a result of the 1970s excavations may still be valid, with the ship operating in the English coastal trade between Bristol and London. There is some evidence to support the identification of the ship as being an international trading vessel, possibly with links to SW France or Iberia.

Martin Read, February 2018

For more information on ongoing research on the Cattewater wreck and the archive project, please visit:



Select Bibliography

Carpenter, A.C., Ellis, K.H. & McKee, J.E.G. 1974 Interim Report on the Wreck Discovered in the Cattewater, Plymouth on 20 June 1973 NMM Maritime Monographs and Reports 13.

Redknap, M. 1984 The Cattewater Wreck: the investigation of an armed vessel of the early 16th century National Maritime Museum Archaeology Series 8/British Archaeological Reports – British Series 131.

Redknap, M. 1997 ‘Reconstructing 16th-century ship culture from a partially excavated site: The Cattewater Wreck:’ in Redknap, M. (ed.) Artefacts from Wrecks Oxbow Monograph 84.

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